What is the recommended treatment for stage II vulvar cancer?

Treatment of Stage II Vulvar Cancer

For stage II vulvar cancer, perform radical partial vulvectomy with inguinofemoral lymph node evaluation—ipsilateral for lateralized tumors (≥2 cm from midline) or bilateral for central/near-midline tumors—followed by adjuvant radiation therapy if lymph nodes are positive. 1

Primary Surgical Treatment Based on Tumor Location

The surgical approach for stage II vulvar cancer is dictated by the tumor's relationship to the vulvar midline 1:

Lateralized Lesions (≥2 cm from midline)

• Perform radical partial vulvectomy with ipsilateral inguinofemoral lymph node evaluation only 1
• Target surgical margins of 1-2 cm if feasible 1
• Resection depth should extend to the urogenital diaphragm 1

Central or Near-Midline Lesions (<2 cm from midline)

• Perform radical partial vulvectomy with bilateral inguinofemoral lymph node evaluation 1
• Bilateral assessment is mandatory due to risk of contralateral lymphatic spread 1

Lymph Node Evaluation Strategy

Sentinel lymph node (SLN) biopsy is the preferred initial approach when specific criteria are met, as it significantly reduces morbidity without compromising oncologic outcomes 1:

Eligibility Criteria for SLN Biopsy

• Unifocal tumor <4 cm in diameter 1, 2
• Clinically and radiologically negative groin nodes 1, 2
• No previous vulvar surgery that disrupted lymphatic drainage 1
• Availability of high-volume experienced surgeon 1
• Use dual tracer technique (technetium-99m radiocolloid plus blue dye) for optimal detection 1

When SLN is Not Detected or Ineligible

• Proceed immediately to complete ipsilateral or bilateral inguinofemoral lymphadenectomy 1
• This is non-negotiable as omitting lymph node evaluation in tumors >1 mm invasion significantly increases recurrence risk 2

Critical Morbidity Considerations

The choice between SLN biopsy and complete lymphadenectomy has profound implications for quality of life:

• Complete inguinofemoral lymphadenectomy carries 30-70% risk of lymphedema and 20-40% risk of wound complications 1, 2
• SLN biopsy reduces lymphedema risk to approximately 5% 2
• Surgical treatment of the groin followed by tailored adjuvant radiation (if node-positive) remains superior to primary groin radiation, which results in higher groin recurrence rates despite lower morbidity 1

Adjuvant Therapy Based on Nodal Status

Node-Positive Disease

Postoperative radiation therapy to the groins is mandatory for all node-positive patients, as this significantly decreases recurrence and improves survival 3, 4:

• Standard dose: 50.4 Gy in 1.8 Gy fractions 3
• Add concurrent platinum-based chemotherapy for high-risk features: multiple positive nodes, extranodal extension, or bulky nodal disease 1, 3
• Chemotherapy options include cisplatin alone, 5-FU + cisplatin, or 5-FU + mitomycin C 3
• Initiate adjuvant treatment within 6-8 weeks post-surgery once adequate healing achieved 3

Management of Unilateral SLN Metastasis

• For lateralized tumors with unilateral SLN metastasis: either complete ipsilateral inguinofemoral lymphadenectomy OR radiation therapy to that groin is acceptable 1, 2
• For midline tumors with unilateral SLN metastasis: unilateral groin treatment acceptable only if contralateral groin has negative sentinel node or negative lymphadenectomy 1

Node-Negative Disease

• Observation is appropriate for patients with negative lymph nodes and no other high-risk primary tumor features 1
• Consider adjuvant vulvar radiation for close margins (<8 mm) where re-excision not feasible, or presence of lymphovascular invasion, large tumor size, or depth of invasion >5 mm 4

Common Pitfalls to Avoid

• Never omit lymph node evaluation in stage II disease—the risk of lymphatic metastases exceeds 8% 1
• Do not perform SLN biopsy if tumor is multifocal or >4 cm—proceed directly to complete lymphadenectomy 1, 2
• Avoid en bloc radical vulvectomy—modern separate incision technique for vulvar tumor and lymph nodes reduces morbidity without compromising survival 3, 5
• Do not delay adjuvant radiation in node-positive patients—groin recurrences are almost universally fatal 4
• A negative unilateral lymphadenectomy carries <3% risk of contralateral metastases, but this applies only to truly lateralized lesions 1

Alternative Approach for Inoperable Patients

For patients unable to undergo surgery due to medical comorbidities, primary radiation therapy may provide benefit, though it results in higher groin recurrence rates than surgical management 1.